Current issues in adjuvant treatment of stage II colon cancer

Complete Obstruction, a Real Risk Factor: A Comprehensive Study on Obstruction in Stage IIA Colon Cancer With Propensity Score Matching Analysis

MICROABSTRACT

This study evaluates the prognostic significance of obstructions in stage IIA colon cancer, distinguishing between partial and complete obstructions. It employs a retrospective review of 1914 patients with propensity score matching to analyze oncologic outcomes. Findings reveal complete obstruction as a significant risk factor for poorer outcomes, emphasizing the necessity for further research to refine treatment strategies, particularly regarding the efficacy of adjuvant chemotherapy across obstruction types.

BACKGROUND

This study examined the prognostic impact of obstructions in stage IIA colon cancer. The analysis specifically differentiated partial and complete obstructions, analyzing their distinct influences of both on oncologic outcomes.

MATERIALS AND METHODS

A retrospective review was conducted of stage IIA colon cancer cases with the presence of an obstruction. Patients were stratified by whether it was partial or complete based on the severity of obstruction. Propensity score matching was employed to control for confounders.

RESULTS

Among 1914 consecutive patients diagnosed with stage IIA colon cancer, 758 patients (597 patients with partial obstruction, 161 patients with complete obstruction) exhibited obstruction, while 1156 patients had no obstruction. The median follow-up period was 126 months. Complete obstruction was associated with poorer disease-free survival (Hazard ratio (HR) = 1.785, P < .001) and overall survival (HR = 1.853, P = .001). This trend persisted after propensity score matching, patients with complete obstruction showing a worsened disease-free survival (HR = 1.666, P = .028) and overall survival (HR = 1.732, P = .041). Adjuvant chemotherapy showed improved outcomes overall, but its efficacy varied across obstruction types.

CONCLUSION

Differentiating between complete and partial obstructions in stage IIA colon cancer is an important clinical distinction, as our findings suggest that complete obstruction is a significant risk factor for poorer oncologic outcomes. While adjuvant chemotherapy generally improves prognosis in stage IIA colon cancer, the correlation of obstruction type with its efficacy remains uncertain, necessitating further research to refine treatment strategies.

A national evaluation of the use and survival impact of adjuvant chemotherapy in Stage II colon cancer from the national cancer database

AIM

Stage II colon cancers are a heterogeneous category, with controversy over use of adjuvant chemotherapy (AC). Patients with high-risk features may benefit from AC to improve overall survival (OS). Current guidelines do not routinely recommend AC in low-risk cases, but the actual use and benefit on OS in this cohort have not been fully examined on a national scale. We aimed to evaluate the use and impact of AC on OS in low-risk Stage II colon cancer.

METHODS

The national cancer database was reviewed for Stage II colon cancers undergoing curative resection (2010-2015). Cases with preoperative radio-chemotherapy or high-risk features were excluded. Cases were stratified into 'AC' and 'no AC' cohorts, and then propensity score matched. Kaplan-Meier and Cox regression analysed OS. The main outcome measures were the incidence and impact of AC on OS in low-risk Stage II colon cancer.

RESULTS

Of 39 926 patients evaluated, 8.2% (n = 3275) received AC. Matching resulted in 3275 cases per cohort. AC significantly improved 1-, 3- and 5-year OS versus no AC (P = 0.0017). The 5-year absolute risk reduction was 2.6%, relative risk reduction 12%, with a number needed to treat of 38. In the Cox model, AC remained significantly associated with increased OS (hazard ratio 0.816; 95% CI 0.713-0.934; P < 0.003).

CONCLUSIONS

From this dataset, AC was associated with improved OS in low-risk Stage II disease. These findings from a large-scale sample question current guidelines and the need for better risk stratification. Further study with more robust variables is warranted to determine AC best practices.

Clinical implication of adjuvant chemotherapy according to mismatch repair status in patients with intermediate-risk stage II colon cancer

Background

The present study evaluated the clinical implications of adjuvant chemotherapy according to the mismatch repair (MMR) status and clinicopathologic features of patients with intermediate- and high-risk stage II colon cancer (CC).

Methods

This study retrospectively reviewed 5,774 patients who were diagnosed with CC and underwent curative surgical resection at Kyungpook National University Chilgok Hospital. The patients were enrolled according to the following criteria: (1) pathologically diagnosed with primary CC; (2) stage II CC classified based on the 7th edition of the American Joint Committee on Cancer staging system; (3) intermediate- and high-risk features; and (4) available test results for MMR status. A total of 286 patients met these criteria and were included in the study.

Results

Among the 286 patients, 54 (18.9%) were identified as microsatellite instability-high (MSI-H) or deficient MMR (dMMR). Although all the patients identified as MSI-H/dMMR showed better survival outcomes, T4 tumors and adjuvant chemotherapy were identified as independent prognostic factors for survival. For the intermediate-risk patients identified as MSI-low (MSI-L)/microsatellite stable (MSS) or proficient MMR (pMMR), adjuvant chemotherapy exhibited a significantly better disease-free survival (DFS) but had no impact on overall survival (OS). Oxaliplatin-containing regimens showed no association with DFS or OS. Adjuvant chemotherapy was not associated with DFS in intermediate-risk patients identified as MSI-H/dMMR.

Conclusion

The current study found that the use of adjuvant chemotherapy was correlated with better DFS in MSI-L/MSS or pMMR intermediate-risk stage II CC patients.

Prognostic Value of Venous Invasion Detected by Elastin Stain May Surpass Lymph Node Status in Colon Cancer

BACKGROUND

Venous invasion is a poor prognostic factor in colon cancer but is often underreported with significant variability.

OBJECTIVES

We aimed to determine the impact of an elastin stain on venous invasion detection in colon cancer and evaluate the value of venous invasion in predicting disease recurrence in combination with lymph node status and other prognostic factors.

DESIGN

This is a retrospective analysis of a prospectively collected database.

SETTING

This study was conducted at a tertiary cancer center.

PATIENTS

A total of 418 patients who underwent curative resection for stage I to III colon cancer and routinely adopted an elastin stain were evaluated.

MAIN OUTCOME MEASURES

Venous invasion detection rate after adopting elastin stain, prognostic factors influencing disease recurrences by multivariate Cox regression models, and survival were measured. The zones of lymph node metastasis were defined as LNZ1, LNZ2, and LNZ3, corresponding to metastases in the pericolic, intermediate, and apical nodes.

RESULTS

Venous invasion detection rate increased from 11.3% to 35.4% compared with the previous period in which only hematoxylin and eosin stain was performed. Cox regression analysis showed venous invasion (HR, 3.856; 95% CI, 1.249-11.910; p = 0.019) and lymph node metastases (HR, 3.156; 95% CI, 1.094-9.108; p = 0.034) in all stages and LNZ 2, 3 (HR, 2.649; 95% CI, 1.244-5.640; p = 0.012) in stage III to be significantly associated with poor disease-free survival. When stratifying all patients by these 3 factors, patients with stage III [LNZ1/venous invasion (-)] had disease-free survival comparable with stage I, but significantly better disease-free survival than those with stage II [venous invasion (+)] (p = 0.018). Patients with stage II [venous invasion (+)] had better disease-free survival by using adjuvant chemotherapy (p < 0.001).

LIMITATIONS

This study was limited by its retrospective design.

CONCLUSION

Elastin stain contributed to a considerable increase in venous invasion detection. Venous invasion can be a powerful predictor of poor disease-free survival beyond lymph node metastases when limited to the pericolic area and is useful for deciding the use of adjuvant chemotherapy in stage II colon cancer. See Video Abstract at http://links.lww.com/DCR/B573.

EL VALOR PRONSTICO DE LA INVASIN VENOSA DETECTADA POR LA TINCIN DE ELASTINA PUEDE SUPERAR EL ESTADO DE LOS GANGLIOS LINFTICOS EN EL CNCER DE COLON

ANTECEDENTES:Invasión venosa (IV) es un factor de mal pronóstico en el cáncer de colon, que frecuentemente no se informa con una variabilidad significativa.OBJETIVOS:Nuestro objetivo fue determinar el impacto de tinción de elastina en la detección de IV en el cáncer de colon y evaluar el valor de IV en la predicción de la recurrencia de la enfermedad en combinación con el estado de los ganglios linfáticos y otros factores pronósticos.DISEÑO:Este es un análisis retrospectivo de una base de datos recopilada prospectivamente.ENTORNO CLINICO:Este estudio se realizó en un centro oncológico de referencia de tercer nivel.PACIENTES:Se valoraron un total de 418 pacientes sometidos a resección curativa por cáncer de colon en estadio I-III utilizando de manera rutinaria una tinción de elastina.PRINCIPALES MEDIDAS DE VALORACION:Se midieron la tasa de detección de IV después de adoptar la tinción de elastina, los factores de pronóstico que influyen en las recurrencias de la enfermedad mediante modelos de regresión de Cox multivariados y la supervivencia. La zona de metástasis ganglionares se definió como, LNZ1, LNZ2 y LNZ3, correspondientes a las metástasis en los ganglios pericólicos, intermedios y apicales, respectivamente.RESULTADOS:La tasa de detección de IV aumentó de 11,3% a 35,4% en comparación con el período anterior en el que solo se realizó tinción con hematoxilina y eosina. El análisis de regresión de Cox mostró VI (razón de riesgo, 3.856; intervalo de confianza [IC] del 95%, 1.249-11.910, p = 0.019) y metástasis en los ganglios linfáticos (razón de riesgo, 3.156; IC del 95%, 1.094-9.108, p = 0.034) en todos los estadios y LNZ 2, 3 (cociente de riesgo, 2.649; IC del 95%, 1.244-5.640, p = 0.012) en el estadio III se asociaron significativamente con una pobre supervivencia libre de enfermedad. Al estratificar a todos los pacientes según estos tres factores, los pacientes con estadio III [LNZ1 / VI (-)] tuvieron una sobrevivencia sin enfermedad (SSE) comparable con el estadio I, pero una supervivencia libre de enfermedad significativamente mejor que aquellos con estadio II [VI (+)] (p = 0,018). Pacientes en estadío II [VI (+)] tuvieron una mejor supervivencia sin enfermedad mediante el uso de quimioterapia adyuvante (p <0,001).LIMITACIONES:Estudio limitado por su diseño retrospectivo.CONCLUSIÓN:La tinción de elastina contribuyó a un aumento considerable en la detección de IV. IV puede ser un poderoso predictor de supervivencia sin enfermedad deficiente más allá de las metástasis de los ganglios linfáticos cuando se limita al área pericólica y es útil para decidir el uso de quimioterapia adyuvante en el cáncer de colon en estadío II. Consulte Video Resumen en http://links.lww.com/DCR/B573. (Traducción-Dr. Adrian Ortega).

Prognostic significance of lymph node count in high-risk node-negative colon carcinoma

BACKGROUND

the prognostic value of the number of lymph nodes isolated (< 12 versus ≥ 12) in the surgical specimen continues to be controversial. In this study, the impact of isolating fewer or more than 12 lymph nodes in stage II colon cancer with a high-risk biologic phenotype was analyzed, such as the presence of perineural invasion.

METHODS

all cases of stage II disease (T3-4N0M0) with perineural invasion (PNI+) were retrospectively identified from a prospective database of patients undergoing surgery for colon cancer. The cohort was divided into two groups depending on the number of lymph nodes isolated (< 12 vs ≥ 12). Apart from clinical and surgical data, the patterns of recurrence, overall (OS) and disease-free survival (DFS) at five and ten years were analyzed.

RESULTS

sixty patients met the inclusion criteria, 31.7 % had < 12 lymph nodes isolated and 68.3 % had more than 12 isolated. There were no clinical or surgical differences between the two groups. OS at five and ten years was significantly lower in the patients with < 12 lymph nodes isolated (84.2 %, 62.7 % vs 94.6 % and 91.6 %, p = 0.01). DFS at five and ten years was 51 % vs 86.5 %, respectively (p = 0.005).

CONCLUSION

the number of lymph nodes isolated (with a cutoff of 12) in stage II colon cancer with PNI+ has prognostic value and should therefore be borne in mind when planning adjuvant chemotherapy.

Clinical Implications of Mismatch Repair Status in Patients With High-risk Stage II Colon Cancer

BACKGROUND/AIM

This study evaluated the clinical significance of the mismatch repair (MMR) status and prognostic factors in patients with high-risk stage II colon cancer (CC).

MATERIALS AND METHODS

This was a retrospective analysis of 237 patients diagnosed with high-risk stage II CC who had test results for MMR status.

RESULTS

Among the 237 patients, 76 (32.1%) were identified as having a microsatellite instability-high (MSI-H) status. No significant differences were identified in disease-free or overall survival according to the MMR status. Moreover, no association was found between the use of adjuvant chemotherapy and survival outcomes of the MSI-H group. In a multivariate survival analysis, the primary tumor location (right-sided versus left-sided, hazard ratio(HR)=0.172, p=0.003) and T-stage (HR=4.764, p=0.005) were identified as independent prognostic factors for disease-free survival.

CONCLUSION

The present study found that the MMR status was neither prognostic nor predictive in patients with high-risk stage II CC.

Prognostic impact of interhospital variation in adjuvant chemotherapy for patients with Stage II/III colorectal cancer: a nationwide study

AIM

Clinical guidelines recommend adjuvant chemotherapy for high-risk patients with Stage II-III colorectal cancer. However, chemotherapeutic administration rates differ significantly between hospitals. We assessed the prognostic benefit of adjuvant chemotherapy in patients with Stage IIb/c colorectal cancer, and the prognostic impact of interhospital variations in the administration of adjuvant chemotherapy for Stage II-III colorectal cancer.

METHOD

We conducted a multicentre, retrospective study of 17 757 patients with Stage II-III colorectal cancer treated between 1997 and 2008 in 23 hospitals in Japan. Hospitals were classified as high-rate (rate > 42.8%) or low-rate (rate ≤ 42.8%), chemotherapy prescribing clinics.

RESULTS

The 5-year overall survival (OS) of patients with Stage II-III colorectal cancer receiving adjuvant chemotherapy was significantly higher than for those not receiving adjuvant chemotherapy (85.7% vs 79.2%, P < 0.01 and 79.9% vs 72.5%, P < 0.01, respectively). For patients with Stage II disease, adjuvant chemotherapy was an independent factor for longer OS (P < 0.01, hazard ratio = 0.71). Both adjuvant chemotherapy and high-rate hospital independently improved OS for patients with Stage III colorectal cancer (both P < 0.01; hazard ratio = 0.68 and 0.87, respectively).

CONCLUSION

Significant prognostic benefit was found for patients with Stage IIb/c colorectal cancer who received adjuvant chemotherapy, with patients who were treated in hospitals with high adjuvant chemotherapy rates demonstrating better prognoses.

Adjuvant Chemotherapy for Stage II and III Colon Cancer Following Complete Resection: A Cancer Care Ontario Systematic Review

The objective of this systematic review was to provide current evidence regarding the use of adjuvant systemic chemotherapy for stage II and III colon cancer following curative intent surgery. MEDLINE and EMBASE databases and proceedings of American Society for Clinical Oncology and European Society of Medical Oncology/European Cancer Congress were searched through to August 2015. Systematic reviews (with or without meta-analyses) and randomised controlled trials were included. Patients with completely resected stage III colon cancer have an overall survival benefit from adjuvant chemotherapy. Combination chemotherapy (5-fluorouracil/leucovorin/oxaliplatin or capecitabine/oxaliplatin) provides a larger benefit than monotherapy but with additional toxicity. For stage II colon cancer, a clear overall survival benefit has not been shown. However, based on the subgroup analysis available, patients with high-risk stage II disease may benefit from adjuvant chemotherapy. Patients younger than 70 years of age may derive greater disease-free survival and overall survival benefit from adjuvant chemotherapy (in combination with oxaliplatin) compared with those older than 70 years. Stage II patients with microsatellite instability may have an overall survival detriment if given adjuvant chemotherapy.

Sentinel lymph node biopsy as a prognostic factor in non-metastatic colon cancer: a prospective study

PURPOSE

Around a third of node-negative patients with colon cancer experience a recurrence after surgery, suggesting poor staging. Sentinel lymph node techniques combined with immunochemistry could improve colon cancer staging. We prospectively assessed the effect of Sentinel node mapping on staging and survival in patients with non-metastatic colon cancer.

METHODS

An observational and prospective study was designed. 105 patients with colon cancer were selected. Patients were classified according to node involvement as: N1, with node invasion detected by the conventional techniques; up-staged, with node invasion detected only by sentinel node mapping; and N0, with negative lymph node involvement by both techniques. Five-year survival and disease-free survival rates were analysed. Multivariate regression analyses were performed to identify prognostic factors for disease-free and overall survival.

RESULTS

Sentinel node mapping was successfully applied in 78 patients: 33 % were N1; 24.5 % were up-staged (18 patients with isolated tumour cells and 1 patient with micrometastases); and 42.5 % were N0. N1 patients had the poorest overall 5-year survival (65.4 %) and 5-year disease-free survival (69.2 %) rates compared with the other two groups. No significant 5-year survival differences were observed between N0 patients (87.9 %) and up-staged patients (84.2 %).

CONCLUSIONS

Patients up-staged after sentinel node mapping do not have a poorer prognosis than patients without node involvement. Detection of isolated cancer cells was not a poor prognosis factor in these patients.

PAK6 increase chemoresistance and is a prognostic marker for stage II and III colon cancer patients undergoing 5-FU based chemotherapy

p21-Activated kinase 6 (PAK6) has been implicated in radiotherapy and docetaxel resistance. We have further evaluated PAK6 as a predictor of 5-fluorouracil (5-FU) treatment response in colon cancer. Here we report that in colon cancer PAK6 promotes tumor progression and chemoresistance both in vitro and in vivo. In the clinical analysis, PAK6 was overexpressed in 104 of 147 (70.75%) stage II and III patients who received 5-FU based chemotherapy after surgery. Multivariate Cox regression analysis indicated that PAK6 was an independent prognostic factor for overall survival (P < 0.001) and disease-free survival (P < 0.001). Colon cancer cell lines showed increased PAK6 expression upon 5-FU treatment. In PAK6-knockdown cells treated with 5-FU, cell viability and phosphorylation of BAD decreased, and the number of apoptotic cells, levels of cleaved caspase 3 and PARP increased compared to control cells. The opposite was observed in PAK6 overexpressing cells. Short hairpin RNA knockdown of PAK6 blocked cells in G2-M phase. Furthermore, Animal experiments results in vivo are consistent with outcomes in vitro. This study demonstrates that PAK6 is an independent prognostic factor for adjuvant 5-FU-based chemotherapy in patients with stage II and stage III colon cancer.

Focus on 16p13.3 Locus in Colon Cancer

Background

With one million new cases of colorectal cancer (CRC) diagnosed annually in the world, CRC is the third most commonly diagnosed cancer in the Western world. Patients with stage I-III CRC can be cured with surgery but are at risk for recurrence. Colorectal cancer is characterized by the presence of chromosomal deletions and gains. Large genomic profiling studies have however not been conducted in this disease. The number of a specific genetic aberration in a tumour sample could correlate with recurrence-free survival or overall survival, possibly leading to its use as biomarker for therapeutic decisions. At this point there are not sufficient markers for prediction of disease recurrence in colorectal cancer, which can be used in the clinic to discriminate between stage II patients who will benefit from adjuvant chemotherapy. For instance, the benefit of adjuvant chemotherapy has been most clearly demonstrated in stage III disease with an approximately 30 percent relative reduction in the risk of disease recurrence. The benefits of adjuvant chemotherapy in stage II disease are less certain, the risk for relapse is much smaller in the overall group and the specific patients at risk are hard to identify.

Materials and Methods

In this study, array-comparative genomic hybridization analysis (array-CGH) was applied to study high-resolution DNA copy number alterations in 93 colon carcinoma samples. These genomic data were combined with parameters like KRAS mutation status, microsatellite status and clinicopathological characteristics.

Results

Both large and small chromosomal losses and gains were identified in our sample cohort. Recurrent gains were found for chromosome 1q, 7, 8q, 13 and 20 and losses were mostly found for 1p, 4, 8p, 14, 15, 17p, 18, 21 and 22. Data analysis demonstrated that loss of chromosome 4 is linked to a worse prognosis in our patients series. Besides these alterations, two interesting small regions of overlap were identified, which could be associated with disease recurrence. Gain of the 16p13.3 locus (including the RNA binding protein, fox-1 homolog gene, RBFOX1) was linked with a worse recurrence-free survival in our patient cohort. On the other hand, loss of RBFOX1 was only found in patients without disease recurrence. Most interestingly, above mentioned characteristics were also found in stage II patients, for whom there is a high medical need for the identification of new prognostic biomarkers.

Conclusions

In conclusion, copy number variation of the 16p13.3 locus seems to be an important parameter for prediction of disease recurrence in colon cancer.

Neoadjuvant FOLFOX 4 versus FOLFOX 4 with Cetuximab versus immediate surgery for high-risk stage II and III colon cancers: a multicentre randomised controlled phase II trial--the PRODIGE 22--ECKINOXE trial

Background

In patients with high risk stage II and stage III colon cancer (CC), curative surgery followed by adjuvant FOLFOX-4 chemotherapy has become the standard of care. However, for 20 to 30 % of these patients, the current curative treatment strategy of surgical excision followed by adjuvant chemotherapy fails either to clear locoregional spread or to eradicate distant micrometastases, leading to disease recurrence. Preoperative chemotherapy is an attractive concept for these CCs and has the potential to impact upon both of these causes of failure. Optimum systemic therapy at the earliest possible opportunity may be more effective at eradicating distant metastases than the same treatment given after the delay and immunological stress of surgery. Added to this, shrinking the primary tumor before surgery may reduce the risk of incomplete surgical excision, and the risk of tumor cell shedding during surgery.

Methods/Design

PRODIGE 22 - ECKINOXE is a multicenter randomized phase II trial designed to evaluate efficacy and feasibility of two chemotherapy regimens (FOLFOX-4 alone and FOLFOX-4 + Cetuximab) in a peri-operative strategy in patients with bulky CCs. Patients with CC deemed as high risk T3, T4 and/or N2 on initial abdominopelvic CT scan are randomized to either colectomy and adjuvant chemotherapy (control arm), or 4 cycles of neoadjuvant chemotherapy with FOLFOX-4 (for RAS mutated patients). In RAS wild-type patients a third arm testing FOLFOX+ cetuximab has been added prior to colectomy. Patients in the neoadjuvant chemotherapy arms will receive postoperative treatment for 4 months (8 cycles) to complete their therapeutic schedule. The primary endpoint of the study is the histological Tumor Regression Grade (TRG) as defined by Ryan. The secondary endpoints are: treatment strategy safety (toxicity, primary tumor related complications under chemotherapy, peri-operative morbidity), disease-free and recurrence free survivals at 3 years, quality of life, carcinologic quality and completeness of the surgery, initial radiological staging and radiological response to neoadjuvant chemotherapy, and the correlation between histopathological and radiological response. Taking into account a 50 % prevalence of CC without RAS mutation, accrual of 165 patients is needed for this Phase II trial.

Trial Registration

NCT01675999 (ClinicalTrials.gov)

Establishment of new predictive markers for distant recurrence of colorectal cancer using lectin microarray analysis

We evaluated the clinical benefits of novel predictive markers for distant recurrence with colorectal cancer using lectin microarray analysis of cell surface glycan modifications. Glycoproteins were extracted from formalin-fixed, paraffin-embedded tumor specimens and normal epithelium from 53 consecutive curatively resected stage I–III colorectal cancer cases and then subjected to lectin microarray to obtain lectin–glycan interaction (LGI) values. In addition, clinicopathological factors associated with distant recurrence were identified. LGI values that were associated with distant recurrence were validated with an additional 55 curatively resected stage II colorectal cancer cases. LGI values for Agaricus bisporus (ABA) lectin, prominent in cancer tissues, were statistically associated with distant recurrence. ABA lectin staining exhibited strikingly intense signals in the cytoplasm and apical surfaces of cancer cells, while weak staining was observed in the supranuclear regions of normal epithelium. This ABA tumor/normal LGI ratio may be a new predictive biomarker for distant recurrence of curatively resected colorectal cancer.

Multivariate analysis of prognostic factors for patients with colon carcinoma

AIM: To investigate the prognostic factors for colon carcinoma by analyzing its clinical and pathological characteristics.

METHODS: We retrospectively reviewed the demographic, clinical, histopathological, and laboratory data for consecutive patients with colon cancer who underwent curative surgery alone from July 2007 to May 2010 at Peking University Cancer Hospital. Unvaried and multivariate analyses were conducted to identify prognostic factors for colon carcinoma.

RESULTS: A total of 226 valid cases were reviewed in this study, and their 3-year overall survival rate was 81.9%. Univariate analysis showed that preoperative CEA level > 5 ng/mL, poor differentiation, age < 40, blood transfusion, higher T stage, higher N stage, metastasis and lymphatic vessel invasion were poor prognostic factors for patients with colon cancer (P < 0.05). Multivariate analysis found that preoperative CEA level (P = 0.017), higher N stage (P = 0.005), poor differentiation (P = 0.002), and higher M stage (P = 0.000) were the independent prognostic factors for colon carcinoma.

CONCLUSION: Based on the prognostic risk factors such as preoperative CEA level, poor differentiation, higher N stage and metastasis, more accurate risk stratification can be conducted in patients with colon cancer. Patients with such risk factors should be considered as candidates for receiving more intensive treatment and surveillance.

The role of sentinel lymph node in colon cancer evolution

INTRODUCTION

The aim of this study is to evaluate the sentinel lymph node mapping (SLNM) with methylene blue staining "ex vivo" in colon cancer, as well as calculate the upstaging obtained by the determination of micrometastases and its correlation with the evolution of the disease.

METHODS

Between 2008 and 2011, 101 patients with colon cancer undergoing resection were studied prospectively with SLNM and detection of micrometastases. The correlation of SLN micrometastases with the disease evolution was evaluated in patients with a follow-up of more than one year.

RESULTS

The SLNM rate was 92 cases (91%). Only SLN was positive for micrometastases in 9 cases, with a 14% upstaging. The incidence of false negatives was 9 patients (10%). Mean follow of N0 patients (n=74) was 38 months. The SLN- (negative) group (65 patients) had a recurrence rate of 4 patients (7%), whereas this rate was 2 patients (22%) in the group of SLN+(positive) (9 patients), but without significant differences. No differences in survival were observed.

CONCLUSIONS

SLNM is a reproducible technique without significant increase in time and costs. Upstaging was obtained in 14% of patients staged as N0 by conventional technique. At follow-up of N0 patients with SLN+there seems to be a higher rate of recurrence, which could change the guidelines of adjuvant treatment, but we must interpret the results it with caution because the sample is small.

Over-expression of the ATP5J gene correlates with cell migration and 5-fluorouracil sensitivity in colorectal cancer

Recently we found that ATP5J was over-expressed in tissue samples from patients with colorectal cancer. However, the clinical significance and function of the over-expression of ATP5J in these patients remains unclear. We investigated these issues in the current study. Our results indicated that expression of ATP5J was significantly higher in colorectal cancer tissue than in adjacent tissue, and it was also significantly higher in metastatic lymph nodes than in primary cancer tissue (P<0.05). A correlation between ATP5J expression and tumor differentiation was detected, but no correlation with gender, age, T stage, lymph node metastasis, or survival status was observed. Down-regulation of ATP5J expression attenuated the ability of cell migration and increased the sensitivity to 5-fluorouracil (5-Fu) in cells of the DLD1 cell line. Inversely, up-regulation of ATP5J expression enhanced cell migration and decreased 5-Fu sensitivity, suggesting that the function of ATP5J in colorectal cancer might involve cell migration and 5-Fu sensitivity.

Independent validation of a prognostic genomic signature (ColoPrint) for patients with stage II colon cancer

OBJECTIVES

The aim of this study was to independently validate a genomic signature developed both to assess recurrence risk in stage II patients and to assist in treatment decisions.

BACKGROUND

Adjuvant therapy is recommended for high-risk patients with stage II colon cancer, but better tools to assess the patients' prognosis accurately are still required.

METHODS

Previously, an 18-gene signature had been developed and validated on an independent cohort, using full genome microarrays. In this study, the gene signature was translated and validated as a robust diagnostic test (ColoPrint), using customized 8-pack arrays. In addition, clinical validation of the diagnostic ColoPrint assay was performed on 135 patients who underwent curative resection (R0) for colon cancer stage II in Munich. Fresh-frozen tissue, microsatellite instability status, clinical parameters, and follow-up data for all patients were available. The diagnostic ColoPrint readout was determined blindly from the clinical data.

RESULTS

ColoPrint identified most stage II patients (73.3%) as at low risk. The 5-year distant-metastasis free survival was 94.9% for low-risk patients and 80.6% for high-risk patients. In multivariable analysis, ColoPrint was the only significant parameter to predict the development of distant metastasis with a hazard ratio of 4.28 (95% confidence interval, 1.36-13.50; P = 0.013). Clinical risk parameters from the American Society of Clinical Oncology (ASCO) recommendation did not add power to the ColoPrint classification. Technical validation of ColoPrint confirmed stability and reproducibility of the diagnostic platform.

CONCLUSIONS

ColoPrint is able to predict the development of distant metastasis of patients with stage II colon cancer and facilitates the identification of patients who may be safely managed without chemotherapy.

Adjuvant therapy in patients with stage II and III colon cancer under 70 years of age

SUMMARY Colorectal cancer is a common malignancy and its prognosis has improved over recent decades due to sustained efforts of the scientific community. This review focuses on adjuvant therapy across the lifespan of patients under 70 years of age. Here, we discuss the standard management of patients with stage III colon cancer, consisting of fluoropyrimidines and oxaliplatin combination for 6 months. The specific issues faced by patients with stage II colon cancer, including adjuvant chemotherapy in high-risk patients, are discussed. Finally, we describe the distinctive characteristics of patients with colon cancer under 40 years of age and the prospects of adjuvant chemotherapy in patients with colon cancer.

Cost-effectiveness of adjuvant FOLFOX and 5FU/LV chemotherapy for patients with stage II colon cancer

PURPOSE

We evaluated the cost-effectiveness of adjuvant chemotherapy using 5-fluorouracil, leucovorin (5FU/LV), and oxaliplatin (FOLFOX) compared with 5FU/LV alone and 5FU/LV compared with observation alone for patients who had resected stage II colon cancer.

METHODS

We developed 2 Markov models to represent the adjuvant chemotherapy and follow-up periods and a single Markov model to represent the observation group. We used calibration to estimate the transition probabilities among different toxicity levels. The base case considered 60-year-old patients who had undergone an uncomplicated hemicolectomy for stage II colon cancer and were medically fit to receive 6 months of adjuvant chemotherapy. We measured health outcomes in quality-adjusted life-years (QALYs) and estimated costs using 2007 US dollars.

RESULTS

In the base case, adjuvant chemotherapy of the FOLFOX regimen had an incremental cost-effectiveness ratio (ICER) of $54,359/QALY compared with the 5FU/LV regimen, and the 5FU/LV regimen had an ICER of $14,584/QALY compared with the observation group from the third-party payer perspective. The ICER values were most sensitive to 5-year relapse probability, cost of adjuvant chemotherapy, and the discount rate for the FOLFOX arm, whereas the ICER value of 5FU/LV was most sensitive to the 5-year relapse probability, 5-year survival probability, and the relapse cost. The probabilistic sensitivity analysis indicates that the ICER of 5FU/LV is less than $50,000/QALY with a probability of 99.62%, and the ICER of FOLFOX as compared with 5FU/LV is less than $50,000/QALY and $100,000/QALY with a probability of 44.48% and 97.24%, respectively.

CONCLUSION

Although adjuvant chemotherapy with 5FU/LV is cost-effective at all ages for patients who have undergone an uncomplicated hemicolectomy for stage II colon cancer, FOLFOX is not likely to be cost-effective as compared with 5FU/LV.

ColoGuidePro: a prognostic 7-gene expression signature for stage III colorectal cancer patients

PURPOSE

Improved prognostic stratification of patients with stage II and III colorectal cancer is warranted for postoperative clinical decision making. This study was conducted to develop a clinically feasible and robust prognostic classifier for these patients independent of adjuvant treatment.

EXPERIMENTAL DESIGN

Global gene expression profiles from altogether 387 stage II and III colorectal cancer tissue samples from three independent patient series were included in the study. ColoGuidePro, a seven-gene prognostic classifier, was developed from a selected Norwegian learning series (n = 95; no adjuvant treatment) using lasso-penalized multivariate survival modeling with cross-validation.

RESULTS

The expression signature significantly stratified patients in a consecutive Norwegian test series, in which patients were treated according to current standards [HR, 2.9 (1.1-7.5); P = 0.03; n = 77] and an external validation series [HR, 3.7 (2.0-6.8); P < 0.001; n = 215] according to survival. ColoGuidePro was also an independent predictor of prognosis in multivariate models including tumor stage in both series (HR, ≥ 3.1; P ≤ 0.03). In the validation series, which consisted of patients from other populations (United States and Australia), 5-year relapse-free survival was significantly predicted for stage III patients only (P < 0.001; n = 107). Here, prognostic stratification was independent of adjuvant treatment (P = 0.001).

CONCLUSIONS

We present ColoGuidePro, a prognostic classifier developed for patients with stage II and III colorectal cancer. The test is suitable for transfer to clinical use and has best prognostic prediction potential for stage III patients.

Recent approaches to identifying biomarkers for high-risk stage II colon cancer

The use of adjuvant chemotherapy for stage II colon cancer remains controversial. The accurate assessment of the risk factors associated with recurrence in patients with stage II disease is the key to identifying the patients that are most likely to benefit from adjuvant chemotherapy. Recent guidelines advocate that adjuvant chemotherapy for high-risk stage II colon cancer should take into account factors such as the T stage, number of lymph nodes examined, tumor differentiation, and tumor perforation. In addition to these clinicopathological factors, there has also been intense interest in the identification of new prognostic or predictive biomarkers that can improve outcomes through better patient classification and selection for adjuvant chemotherapy. Recent advances in the field of molecular genetics have led to the identification of specific biomarkers involved in colorectal cancer progression, whereas gene expression microarray technology has led to the identification of molecular profiles able to predict recurrence or benefit from adjuvant chemotherapy. However, none of these has yet been validated in large prospective clinical trials. In this article, we review the current status of prognostic and predictive biomarkers for stage II colon cancer and provide an update on the most recent developments.

Adjuvant therapy with fluorouracil and oxaliplatin in stage II and elderly patients (between ages 70 and 75 years) with colon cancer: subgroup analyses of the Multicenter International Study of Oxaliplatin, Fluorouracil, and Leucovorin in the Adjuvant Treatment of Colon Cancer trial

PURPOSE

Oxaliplatin combined with fluoropyrimidine improves survival in patients with stage III colon cancer. However, adjuvant chemotherapy with oxaliplatin is controversial in stage II and elderly patients.

PATIENTS AND METHODS

We performed subgroup analyses of stage II and elderly patients randomly assigned fluorouracil with leucovorin (FL) ± oxaliplatin (FOLFOX4) in the Multicenter International Study of Oxaliplatin/Fluorouracil/Leucovorin in the Adjuvant Treatment of Colon Cancer study. Comorbidities, severe adverse events, second cancers, management of relapse and death as a result of causes than other colon cancer were studied.

RESULTS

Two thousand two hundred forty-six patients were enrolled. Overall, 899 patients had stage II disease, including 330 low-risk and 569 high-risk patients. A total of 315 patients were ages 70 to 75 years. For stage II patients, the hazard ratio (HR) for comparing FOLFOX4 with FL was 0.84 (95% CI, 0.62 to 01.14) for disease-free survival (DFS), 0.70 (95% CI, 0.49 to 0.99) for time to recurrence (TTR), and 1.00 (95% CI, 0.70 to 1.41) for overall survival (OS). There was no interaction between treatment and stage or age. Low-risk stage II patients did not benefit from oxaliplatin. In high-risk stage II patients, the HR comparing FOLFOX4 with FL was 0.72 (95% CI, 0.51 to 1.01) for DFS, 0.62 (95% CI, 0.41 to 0.92) for TTR, and 0.91 (95% CI, 0.61 to 1.36) for OS. In elderly patients, the HR comparing FOLFOX4 with FL was 0.93 (95% CI, 0.64 to 1.35) for DFS, 0.72 (95% CI, 0.47 to 1.11) for TTR, and 1.10 (95% CI, 0.73 to 1.65) for OS.

CONCLUSION

The results of these subset analyses show no statistically significant benefit (OS and DFS) for the addition of oxaliplatin to FL as adjuvant treatment for either stage II and elderly patients.

Analyzing proteasomal subunit expression reveals Rpt4 as a prognostic marker in stage II colorectal cancer

Colorectal cancer is a leading cause of cancer-related deaths worldwide. Early diagnosis and treatment of colorectal cancer is the key to improving survival rates and as such a need exists to identify patients who may benefit from adjuvant chemotherapy. The dysregulation of the ubiquitin-proteasome system (UPS) has been implicated in oncogenesis and cancer cell survival, and proteasome inhibitors are in clinical use for a number of malignancies including multiple myeloma. In our study, we examined the protein expression of several key components of the UPS in colorectal cancer using immunohistochemistry to determine expression levels of ubiquitinylated proteins and the proteasomal subunits, 20S core and Rpt4 in a cohort of 228 patients with colon cancer. Multivariate Cox analysis revealed that neither the intensity of either ubiquitinylated proteins or the 20S core was predictive in either Stage II or III colon cancer for disease free survival or overall survival. In contrast, in Stage II patients increased Rpt4 staining was significantly associated with disease free survival (Cox proportional hazard ratio 0.605; p = 0.0217). Our data suggest that Rpt4 is an independent prognostic variable for Stage II colorectal cancer and may aid in the decision of which patients undergo adjuvant chemotherapy.

Cost of care for colorectal cancer in Ireland: a health care payer perspective

OBJECTIVE

Management options for colorectal cancer have expanded in recent years. We estimated average lifetime cost of care for colorectal cancer in Ireland in 2008, from the health care payer perspective.

METHOD

A decision tree model was developed in Microsoft EXCEL. Site and stage-specific treatment pathways were constructed from guidelines and validated by expert clinical opinion. Health care resource use associated with diagnosis, treatment and follow-up were obtained from the National Cancer Registry Ireland (n=1,498 cancers diagnosed during 2004-2005) and three local hospital databases (n=155, 142 and 46 cases diagnosed in 2007). Unit costs for hospitalisation, procedures, laboratory tests and radiotherapy were derived from DRG costs, hospital finance departments, clinical opinion and literature review. Chemotherapy costs were estimated from local hospital protocols, pharmacy departments and clinical opinion. Uncertainty was explored using one-way and probabilistic sensitivity analysis.

RESULTS

In 2008, the average (stage weighted) lifetime cost of managing a case of colorectal cancer was €39,607. Average costs were 16% higher for rectal (€43,502) than colon cancer (€37,417). Stage I disease was the least costly (€23,688) and stage III most costly (€48,835). Diagnostic work-up and follow-up investigations accounted for 4 and 5% of total costs, respectively. Cost estimates were most sensitive to recurrence rates and prescribing of biological agents.

CONCLUSION

This study demonstrates the value of using existing data from national and local databases in contributing to estimating the cost of managing cancer. The findings illustrate the impact of biological agents on costs of cancer care and the potential of strategies promoting earlier diagnosis to reduce health care resource utilisation and care costs.

Prognostic relevance of occult metastases detected by cytokeratin 20 and mucin 2 mRNA levels in sentinel lymph nodes from colon cancer patients

PURPOSE

To investigate the prognostic value of occult metastases detected by quantitative measurements of candidate biomarkers in sentinel lymph nodes (SLNs) from patients curatively resected for colon cancer.

METHODS

Resection specimens from consecutive patients undergoing surgery for localized colon cancer were subjected to ex vivo SLN mapping. SLNs were examined for the presence of metastases by routine hematoxylin-erythrosin-safranin staining and by cytokeratin 20 (CK20) and mucin 2 (MUC2) mRNA quantification. The patients were stratified according to KRAS and BRAF mutation status and microsatellite instability status in their primary tumors. Survival end points were analyzed by Kaplan-Meier survival estimates and log-rank tests.

RESULTS

A total of 817 SLNs were identified in 206 (97 %) of the 213 included patients. Routine histological examination of SLNs and other regional lymph nodes identified 63 patients with positive nodes (pN+), of which 42 (67 %) were positive in one or more SLNs (sensitivity 67 %, false-negative rate 33 %). On the basis of the CK20 and MUC2 mRNA levels in SLNs, occult metastases were suggested in 86 (60 %) and 52 (36 %) of the 143 otherwise LN-negative (pN0) patients, respectively. Survival analysis with a median 3.6-year follow-up revealed that MUC2 mRNA quantification had significant prognostic value in SLNs from all patients; however, occult SLN metastasis detection did not.

CONCLUSIONS

Occult SLN metastases detected by CK20 and MUC2 mRNA quantification had limited prognostic value.

GUCY2C molecular staging personalizes colorectal cancer patient management

While the most significant prognostic and predictive marker in the management of colorectal cancer patients is cancer cells in regional lymph nodes, approximately 30% of patients whose lymph nodes are ostensibly free of tumor cells by histopathology ultimately develop recurrent disease reflecting occult metastases. Molecular techniques utilizing highly specific markers and ultra-sensitive detection technologies have emerged as powerful staging platforms to establish prognosis and predict responsiveness to chemotherapy in colorectal cancer patients. This review describes the evolution of the tumor suppressor GUCY2C as a prognostic and predictive molecular biomarker that quantifies occult tumor burden in regional lymph nodes for staging patients with colorectal cancer.

Molecular staging individualizing cancer management

Although the most important prognostic and predictive marker in colorectal cancer is tumor cells in lymph nodes, approximately 30% of patients who are node-negative die from occult metastases. Molecular staging employing specific markers and sensitive detection technologies has emerged as a powerful platform to assess prognosis in node-negative colon cancer. Integrating molecular staging into algorithms that individualize patient management will require validation and the definition of relationships between occult tumor cells, prognosis, and responses to chemotherapy.

Isolated tumor cells in regional lymph nodes as relapse predictors in stage I and II colorectal cancer

PURPOSE

Lymph node (LN) involvement is the most important prognostic factor in colorectal cancer (CRC), and pN-positive status identifies patients who require adjuvant chemotherapy. Approximately 15% to 20% of patients without nodal metastases (pN0) develop recurrent disease. In this study, we tested the prognostic significance of isolated tumor cells (ITCs) in LNs of patients with pN0 CRC (stages I and II).

PATIENTS AND METHODS

ITCs in LNs regional to CRC were assessed in 312 consecutive patients with pN0 CRC who were followed up clinically and/or endoscopically for at least 6 months after surgery (mean, 67 months; median, 64 months; range, 8 to 102 months). LNs were dissected from gross surgical specimens according to a standardized protocol (with a mean of 17 LNs per patient; range, five to 107 LNs). In all, 5,313 pN0 LNs were collected and assessed by using cytokeratin immunostaining in two serial histology sections from each LN, which amounting to a total of 10,626 specimens. The correlation between ITC status and cancer recurrence was tested by using univariate and multivariate statistics.

RESULTS

ITCs were documented in 185 of 312 patients (59%). CRC relapsed in 31 of 312 patients (10%), and 25 of 31 recurrences (81%) were documented among ITC-positive patients. CRC recurrence rates among ITC-positive and ITC-negative patients were 14% (25 of 185 patients) and 4.7% (six of 127 patients), respectively. In both univariate and multivariate analyses, ITC status was the only variable significantly associated with cancer relapse (Cox model; hazard ratio, 3.00; 95% CI, 1.23 to 7.32; P = .013).

CONCLUSION

In patients with pN0 CRC, cancer relapse was significantly associated with ITCs in regional LNs. ITCs should be considered among the clinicobiologic variables that identify high-risk patients who can benefit from adjuvant chemotherapy.

PIK3CA kinase domain mutation identifies a subgroup of stage III colon cancer patients with poor prognosis

BACKGROUND

PIK3CA mutations in the helical domain (in exon 9) and in the kinase domain (exon 20) cause tumor formation by different means. We aimed to determine the effects of each of these mutations on survival of colon carcinoma patients.

METHODS

A large cohort of 685 colon carcinoma patients was tested for PIK3CA mutations in exons 9 and 20 by single nucleotide primer extension (N = 428) or by real time PCR (N = 257).

RESULTS

PIK3CA mutation rate was 13%. 66 of 83 (79.5%) were in exon 9 and 17 of 83 (20.5%) in exon 20. In survival analysis, PIK3CA mutations in exon 9 and 20 had different effects on patient outcome. The PIK3CA exon 20 mutation conferred a poorer disease free survival compared to patients with wild type alleles and exon 9 mutations (Log rank p = 0.04 and p = 0.03 respectively) and cancer specific survival (Log rank p = 0.03 and p = 0.056 respectively) in stage III patients. In stage I and II this negative effect on outcome was not seen.

CONCLUSIONS

PIK3CA mutation in exon 20 is a negative prognostic factor in stage III colon cancer patients. Moreover, this negative effect is not present in stage I and II patients.

Optimal use of adjuvant chemotherapy in stage II colorectal cancer

BACKGROUND AND OBJECTIVE

The prognosis of stage II colorectal cancer varies. Whether or not to perform adjuvant chemotherapy on patients with stage II colorectal cancer is a controversial issue. The aims of this study were to identify relevant risk factors for the prognosis of stage II colorectal cancer and to evaluate the need for adjuvant chemotherapy.

METHOD

Between January 2000 and January 2005, 443 patients with stage II colorectal cancer who had received radical surgery at the Sun Yat-sen University Cancer Center were retrospectively analyzed. The overall survival rates and survival curves were analyzed using the Kaplan-Meier method and log-rank test. Univariate and multivariate prognostic analyses were performed using the Cox regression model. Patients with certain important risk factors were analyzed according to whether they received adjuvant chemotherapy, and four chemotherapeutic regimens were classified into sub-groups and analyzed.

RESULTS

Univariate analyses showed that intestinal obstruction or perforation, type 2 diabetes mellitus, an inadequate surgical margin, and sampling of less than 12 lymph nodes were risk factors that correlated with poor prognosis. Patients with an intestinal obstruction or perforation and insufficient lymph node samples achieved higher 5-year survival rates with adjuvant chemotherapy than with surgery alone.

CONCLUSION

Intestinal obstruction or perforation, sampling of less than 12 lymph nodes, and inadequate surgical margins were identified as risk factors for poor survival, and patients with either of the first two factors benefited from adjuvant chemotherapy. Moreover, the use of capecitabine alone may be insufficient for patients with an intestinal obstruction or perforation.

Evaluation of lymph node numbers for adequate staging of Stage II and III colon cancer

BACKGROUND

Although evaluation of at least 12 lymph nodes (LNs) is recommended as the minimum number of nodes required for accurate staging of colon cancer patients, there is disagreement on what constitutes an adequate identification of such LNs.

METHODS

To evaluate the minimum number of LNs for adequate staging of Stage II and III colon cancer, 490 patients were categorized into groups based on 1-6, 7-11, 12-19, and ≥ 20 LNs collected.

RESULTS

For patients with Stage II or III disease, examination of 12 LNs was not significantly associated with recurrence or mortality. For Stage II (HR = 0.33; 95% CI, 0.12-0.91), but not for Stage III patients (HR = 1.59; 95% CI, 0.54-4.64), examination of ≥20 LNs was associated with a reduced risk of recurrence within 2 years. However, examination of ≥20 LNs had a 55% (Stage II, HR = 0.45; 95% CI, 0.23-0.87) and a 31% (Stage III, HR = 0.69; 95% CI, 0.38-1.26) decreased risk of mortality, respectively. For each six additional LNs examined from Stage III patients, there was a 19% increased probability of finding a positive LN (parameter estimate = 0.18510, p < 0.0001). For Stage II and III colon cancers, there was improved survival and a decreased risk of recurrence with an increased number of LNs examined, regardless of the cutoff-points. Examination of ≥7 or ≥12 LNs had similar outcomes, but there were significant outcome benefits at the ≥20 cutoff-point only for Stage II patients. For Stage III patients, examination of 6 additional LNs detected one additional positive LN.

CONCLUSIONS

Thus, the 12 LN cut-off point cannot be supported as requisite in determining adequate staging of colon cancer based on current data. However, a minimum of 6 LNs should be examined for adequate staging of Stage II and III colon cancer patients.

[Multimodality therapy of colorectal cancer]

Adjuvant chemotherapy for resected stage III colon cancer is indicated for all patients, including elderly patients >70 years. In general, adjuvant oxaliplatin-fluoropyrimidine chemotherapy should be started within 6 weeks after tumor resection and should be given for a period of 6 months. However, patients aged >70 should receive fluoropyrimidine mono-chemotherapy. This mono-therapy, but not an oxaliplatin-based combination, can also be considered for patients with standard risk stage II tumors without microsatellite instability. In stage II patients with a high risk constellation adjuvant oxaliplatin-fluoropyrimidine combination therapy should be considered. Patients with stage II and III rectal cancer require neoadjuvant radiochemotherapy with fluoropyrimidine followed by adjuvant fluoropyrimidine treatment. There is no role for the use of VEGF- or EGFR-antibodies in the adjuvant therapy of colon cancer or in neoadjuvant therapy of rectal cancer. The prognosis of patients with primary resectable colorectal liver metastases may be improved by adjuvant or perioperative chemotherapy, while neoadjuvant systemic chemotherapy frequently facilitates potential curative resection of initially non-resectable liver metastases.

Lymph node micrometastases and isolated tumor cells influence survival in stage I and II colon cancer

PURPOSE

Lymph-node status is considered the most important prognostic factor in colorectal cancer. The aim of the present prospective study was to evaluate the influence of micrometastases and isolated tumor cells on recurrence and disease-free survival in colon cancer.

METHODS

A total of 193 patients with colon cancer, operated on between 2000 and 2005, were enrolled in the study. All lymph nodes were examined by routine microscopy in hematoxylin and eosin-stained sections. If no metastases were identified in any node, all nodes were examined immunohistochemically with monoclonal antibody CAM 5.2.

RESULTS

Ordinary metastases were found in 67 patients, leaving 126 patients in stage I/II. Immunohistochemistry showed that 5% (6/126) of these had micrometastases and 26% (33/126) had isolated tumor cells. A median of 5 years of follow-up revealed local or distant recurrence in 23% (9/39) of stage I/II patients with micrometastases or isolated tumor cells, compared with 7% (6/87) without micrometastases or isolated tumor cells (P = .010). Five-year disease-free survival for patients with and without micrometastases or isolated tumor cells was 75% and 93%, respectively (P = .012). When analyzed separately, patients with isolated tumor cells (excluding micrometastases) had also lower survival than node-negative patients (P = .012).

CONCLUSION

The presence of micrometastases and isolated tumor cells was found to be a prognostic factor for recurrence and disease-free survival. This may have implications for future treatment of stage I/II colon cancer.

Anastomotic leakage contributes to the risk for systemic recurrence in stage II colorectal cancer

PURPOSE

In stage II colorectal cancer (CRC), high-risk patient selection is required, but no candidate markers have been elucidated. Our concern was whether anastomotic leakage (Lk) is a potential available clinicopathological factor for selecting high-risk stage II.

METHODS

Two hundred seven patients with stage II CRC who underwent curative resection were analyzed. Clinical variables were tested for their relationship to survival.

RESULTS

The 5-year disease-free survival rate (DFS) was 87.0%. The univariable prognostic analyses indicated that Lk (P = 0.003) was the only significant factor. The multivariable prognostic analysis revealed that Lk remained to be potently independent [hazard ratio (HR), 4.21, P = 0.021), and the DFS was 58.3% in cases with Lk, while 88.7% in the counterpart. The multivariable logistic regression analysis revealed perioperative blood transfusion (P = 0.001) was independently associated with Lk. Intriguingly, Lk was closely associated with hematogenic recurrence (P = 0.003) rather than peritoneal or local recurrence. Although sustained increase of the serum C-reactive protein at 2 weeks after operation predicted poor prognosis, the mutitivariable analysis including the C-reactive protein level revealed that Lk still indicated the prognostic potential (HR, 3.70, P = 0.075).

CONCLUSIONS

The findings concluded that Lk may be a high risk for systemic recurrence in stage II CRC.

Prognostic factors in node-negative colorectal cancer: a retrospective study from a prospective database

PURPOSE

There is a need to identify a subgroup of high-risk patients with node-negative colorectal cancer who have a poor long-term prognosis and may benefit from adjuvant therapies. The aim of this study was to evaluate the prognostic impact of clinical and pathological parameters in a retrospective study from a prospective, continuous database of homogenously treated patients.

METHODS

This study included 362 patients operated in a single institution for Dukes A and B (node-negative) colorectal cancer. The median follow-up was 140 months. The prognostic value of 13 clinical and pathological parameters was investigated.

RESULTS

Multivariate analysis identified six independent prognostic factors: age at time of diagnosis (hazard ratio (HR) = 1.076), number of lymph nodes removed (HR = 0.948), perineural invasion (HR = 2.173), venous invasion (HR = 1.959), lymphatic vessel invasion (HR = 2.126), and T4 stage (HR = 5.876).

CONCLUSION

These parameters could be useful in identifying patients with high-risk node-negative colorectal cancer who should be presented to adjuvant therapy.

Carcinoma obstruction of the proximal colon cancer and long-term prognosis--obstruction is a predictor of worse outcome in TNM stage II tumor

PURPOSE

Colon obstruction is suggested to be a predictor of poor outcome in colon cancer. However, the effect of obstruction on outcome in patients with different tumor-nodes-metastases (TNM) stage cancer has not been fully addressed. The aim of this study is to determine whether colon obstruction predicts surgical and long-term oncologic outcomes in patients with proximal colon cancer.

METHODS

A total of 1,492 consecutive patients underwent open resection of primary adenocarcinoma of right colon in a single institution between January 1995 and December 2005. Clinical and follow-up data were extracted from a prospective colorectal cancer database. Univariate and multivariate analyses were performed to identify colon obstruction and other predictors of surgical and oncologic outcomes.

RESULTS

Among 1,492 patients, 306 (20.5%) patients presented with colon obstruction. The rates of surgical morbidity and mortality were greater in patients with an obstruction as compared to patients without an obstruction (22.2% and 3.9% vs. 14.1% and 1.9%; p = 0.0005 and 0.041, respectively). Obstruction predicted a worse long-term disease-free survival (DFS) among patients with stage II-III disease (log-rank test, p = 0.0003). The data were stratified by TNM stage. Obstruction predicted a worse DFS among patients with TNM stage II cancer (598 patients; log-rank test, p = 0.001; Cox regression, p = 0.012), but it was not a predictor in TNM stage III cancer patients (424 patients; p = 0.116; p = 0.108).

CONCLUSIONS

Colon obstruction was an independent predictor of long-term outcome only in TNM stage II but not in stage III proximal colon cancer. Patients with TNM stage II obstructive colon cancer could be included in future trials of adjuvant therapies.

Clinical significance of human kallikrein7 gene expression in colorectal cancer

BACKGROUND

The human kallikrein-related peptidases (KLK) are considered important prognostic biomarkers in cancer. The aim of the current study is to demonstrate gene expression of KLK7 in colorectal cancer (CRC) and to correlate the relative KLK7 expression level with clinicopathological factors of CRC.

METHODS

KLK7 messenger RNA (mRNA) expression was examined in nine CRC cancer cell lines by real-time polymerase chain reaction. The expression levels of KLK7 mRNA in cancerous tissues (n = 136) and paired normal tissues (n = 136) of CRC patients were also examined.

RESULTS

Six of the nine cell lines expressed the KLK7 gene. KLK7 mRNA expression levels in cancer tissues were significantly higher than those in normal tissues. Multivariate analysis revealed that the KLK7 mRNA expression level in cancer was an independent prognostic factor, especially in liver metastasis.

CONCLUSIONS

We provide evidence suggesting that KLK7 mRNA expression is correlated with prognosis in CRC patients, especially in liver metastasis.

Analysis of post-operative changes in serum protein expression profiles from colorectal cancer patients by MALDI-TOF mass spectrometry: a pilot methodological study

BACKGROUND

Mass spectrometry-based protein expression profiling of blood sera can be used to discriminate colorectal cancer (CRC) patients from unaffected individuals. In a pilot methodological study, we have evaluated the changes in protein expression profiles of sera from CRC patients that occur following surgery to establish the potential of this approach for monitoring post-surgical response and possible early prediction of disease recurrence.

METHODS

In this initial pilot study, serum specimens from 11 cancer patients taken immediately prior to surgery and at approximately 6 weeks following surgery were analysed alongside 10 normal control sera by matrix-assisted laser desorption ionisation time of-flight-mass spectrometry (MALDI-TOF MS). Using a two-sided t-test the top 20 ranked protein peaks that discriminate normal from pre-operative sera were identified. These were used to classify post-operative sera by hierarchical clustering analysis (Spearman's Rank correlation) and, as an independent 'test' dataset, by k-nearest neighbour and weighted voting supervised learning algorithms.

RESULTS

Hierarchical cluster analysis classified post-operative sera from all six early Dukes' stage (A and B) patients as normal. The remaining five post-operative sera from more advanced Dukes' stages (C1 and C2) were classified as cancer. Analysis by supervised learning algorithms similarly grouped all advanced Dukes' stages as cancer, with four of the six post-operative sera from early Dukes' stages being classified as normal (P = 0.045; Fisher's exact test).

CONCLUSIONS

The results of this pilot methodological study illustrate the proof-of-concept of using protein expression profiling of post-surgical blood sera from individual patients to monitor disease course. Further validation on a larger patient cohort and using an independent post-operative sera dataset would be required to evaluate the potential clinical relevance of this approach. Prospective data, including follow-up on patient survival, could in the future, then be evaluated to inform decisions on individualised treatment modalities.

Thymidilate synthase expression predicts longer survival in patients with stage II colon cancer treated with 5-flurouracil independently of microsatellite instability

BACKGROUND

5-Fluorouracil (5-FU) is the most commonly used therapeutic agent for colon cancer treatment. Several studies have evaluated in patients with colon cancer, either the role of genes involved in the 5-FU pathway, such as thymidylate synthase (TS), thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) or the role of microsatellite instability (MSI) as prognostic or predictive markers for adjuvant chemotherapy efficacy, with discordant results. In this study we investigated the combined effect of TS, TP, DPD mRNA expression and MSI status in primary tumors of patients with colon cancer, all treated with 5-FU adjuvant therapy.

METHODS

TS, TP and DPD expression levels were investigated by real-time quantitative RT-PCR on RNA extracts from formalin-fixed and paraffin-embedded tissues of 55 patients with colon adenocarcinoma. In the same case study MSI status was assessed on DNA extracts.

RESULTS

A higher TS expression was significantly associated with a longer survival for patients with cancers of stage II (P < 0.01), but not for those with stage III (P = 0.68). In addition, in multivariate analysis, a higher TS expression was significantly associated with a decreased risk of death (HR 0.13, 95% CI 0.03-0.59, P < 0.01), while the MSI status did not have effects on patients' survival.

CONCLUSIONS

This retrospective investigation suggests that TS gene expression at mRNA level can be a useful marker of better survival in patients (especially of those with cancers of stage II) receiving 5-FU adjuvant chemotherapy, independently of the MSI status.

Predictors of occult nodal metastasis in colon cancer: results from a prospective multicenter trial

BACKGROUND

The relationship between primary colon cancer and occult nodal metastases (OMs) detected by cytokeratin immunohistochemistry (CK-IHC) is unknown. We sought to investigate the correlation of clinicopathologic features of colon cancer with OMs and to identify predictors of OM.

METHODS

Patients with colon cancer from 5 tertiary referral cancer centers enrolled in a prospective trial of staging had standard pathologic analysis performed on all resected lymph nodes (using hematoxylin and eosin staining [H&E]). Nodes negative on H&E underwent CK-IHC to detect OMs, which were defined as micrometastases (N1mic) or isolated tumor cells (N0i+). Patients who were negative on both H&E and CK-IHC were defined as node negative (NN), and those positive on H&E were node positive (NP). The relationships between tumor characteristics and OMs were analyzed using the Kruskal-Wallis and the Fisher exact test.

RESULTS

OMs were identified in 23.4% (25/107) of patients. No significant differences were found in demographics, tumor location, tumor size, and number of nodes examined between groups. Compared with the NN group, patients with OMs had more tumors that were T3/T4 (72% vs 57%; P < .001), had tumors of higher grade (28% vs 12%; P = .022), and had tumors with lymphovascular invasion (16% vs 3%; P < .001).

CONCLUSION

Adverse primary pathologic colon cancer characteristics correlate with OMs. In patients with negative nodes on H&E and stage T3/T4 colon cancer, lymphovascular invasion, or high tumor grade, consideration should be given to performing CK-IHC. The detection of OMs in this subset may influence decisions regarding adjuvant chemotherapy and risk stratification.

Development and progression of colorectal neoplasia

A variety of genetic and molecular alterations underlie the development and progression of colorectal neoplasia (CRN). Most of these cancers arise sporadically due to multiple somatic mutations and genetic instability. Genetic instability includes chromosomal instability (CIN) and microsatellite instability (MSI), which is observed in most hereditary non-polyposis colon cancers (HNPCCs) and accounts for a small proportion of sporadic CRN. Although many biomarkers have been used in the diagnosis and prediction of the clinical outcomes of CRNs, no single marker has established value. New markers and genes associated with the development and progression of CRNs are being discovered at an accelerated rate. CRN is a heterogeneous disease, especially with respect to the anatomic location of the tumor, race/ethnicity differences, and genetic and dietary interactions that influence its development and progression and act as confounders. Hence, efforts related to biomarker discovery should focus on identification of individual differences based on tumor stage, tumor anatomic location, and race/ethnicity; on the discovery of molecules (genes, mRNA transcripts, and proteins) relevant to these differences; and on development of therapeutic approaches to target these molecules in developing personalized medicine. Such strategies have the potential of reducing the personal and socio-economic burden of CRNs. Here, we systematically review molecular and other pathologic features as they relate to the development, early detection, diagnosis, prognosis, progression, and prevention of CRNs, especially colorectal cancers (CRCs).

Molecular staging estimates occult tumor burden in colorectal cancer

Tumor cells in regional lymph nodes are a key prognostic marker of survival and predictive marker of response to adjuvant chemotherapy in colorectal cancer. However, clinicopathologic techniques to detect lymph node metastases remain imperfect, and approximately 30% of patients with lymph nodes negative by histology (pN0) develop recurrent disease, reflecting occult metastases that escape detection. These observations underscore an unmet clinical need for accurate approaches to identify occult nodal metastases in colorectal cancer patients. GUCY2C is a receptor whose expression normally is restricted to intestinal epithelial cells, but is universally overexpressed by colorectal cancer cells. A prospective, multicenter, blinded clinical trial established the prognostic utility of GUCY2C qRT-PCR to detect occult nodal metastases in pN0 colorectal cancer patients. Molecular staging revealed that approximately 13% of pN0 patients were free of cancer cells, while approximately 87% had GUCY2C results that suggested occult metastases. The presence of occult nodal metastases was the most powerful independent predictor of time to recurrence and disease-free survival. These observations establish the utility of molecular detection of occult nodal metastases for assessing prognostic risk in pN0 colorectal cancer patients. Advancing GUCY2C into staging paradigms in clinical laboratories will require validation in independent patient populations, definition of the relationship between the quantity of occult tumor metastases and risk, and determination of the utility of GUCY2C qRT-PCR to identify pN0 patients who might benefit from adjuvant chemotherapy.